function valida_data(data){         
    var re = /^(\d{1,2})\/(\d{1,2})\/(\d{4})$/;
    if(data != ''){
    	if(regs = data.match(re)) {
        	if(regs[1] < 1 || regs[1] > 31) {          
	          return false;
    	    }
        	if(regs[2] < 1 || regs[2] > 12) {
	          return false;
    	    }
	        if(regs[3] < 1902 || regs[3] > (new Date()).getFullYear()) {
    	      return false;
	        }
    	}else{        
       		return true;
       	}
	}
	return true;
}
